A Gestão da Qualidade do Serviço Hoteleiro em Cabo Verde: Estruturação de Processos

O trabalho que aqui propomos foi desenvolvido numa perspectiva sociológica, procurando à luz da teoria de estruturação de Giddens analisar a estruturação de um serviço para a qualidade nos hotéis, partindo das perspectivas dos agentes internos. O que ambicionamos com esta tese é analisar a produção do serviço hoteleiro enquanto sistema constituída por práticas recíprocas entre agentes, sujeitos a regras, recursos, constrangimentos e oportunidades. Na óptica que seguimos, a estruturação para um serviço da qualidade depende das regras e recursos mobilizadas e permitidas no decorrer de práticas situadas de agentes intencionados. As estruturas do sistema da qualidade, como nós as entendemos aqui, à luz da dualidade da estrutura, reproduzem-se e participam na produção de novas estruturas e, recursivamente, organizam as práticas e os modos de fazer. Através da significação, legitimação e dominação, dimensões nas quais se desenvolvem os processos sociais de construção dos sistemas da qualidade, procuramos compreender o processo de estruturação de um serviço de qualidade nos hotéis. É com este olhar, que analisamos a estruturação da qualidade nas organizações. Mais do que o aspecto da qualidade enquanto disciplina da gestão, interessa-nos o aspecto da qualidade enquanto resultado de definições sociais construídas e partilhadas através das práticas quotidianas, onde se dá a negociação de significados e atribuição de sentidos às nossas actividades. Interessa-nos analisar a estruturação de um serviço para a qualidade, numa organização, através do estudo das práticas, rotinas, processos, expedientes e racionalidades na relação diária entre os agentes no seio dos hotéis. Analisamos o sistema da qualidade enquanto sistema social envolvendo actividades de sujeitos humanos, localizados no espaço e no tempo (Giddens, 2000). Através da dualidade da estrutura, em que os agentes são possuidores de regras e recursos que durante e através das suas actividades reproduzem e criam as condições para tornarem as mesmas possíveis (Giddens, 1999), procuramos entender a prestação dos serviços. Desta forma analisamos o funcionamento das interacções diárias e das suas regras enquanto meio e produto do sistema da qualidade.

Concepções, Práxis e Tendências de Desenvolvimento Curricular no Ensino Superior Público em Cabo Verde: um Estudo de Caso Sobre a Universidade de Cabo Verde

A tese enquadra-se nas discussões sobre as concepções do currículo, como problemática central nos processos de educação e formação, e o papel da Universidade ao longo dos tempos, mormente nos contextos actuais da globalização, conferindo especial relevo às concepções, práxis e tendências que caracterizam a experiência de desenvolvimento curricular na Universidade de Cabo Verde (Uni-CV), desde a sua criação, em Novembro de 2006, no seguimento de um percurso de quase três décadas do ensino superior público cabo-verdiano Com o enquadramento teórico da problemática da investigação faz-se uma ampla cartografia da literatura relevante no campo científico dos estudos curriculares, numa abordagem que patenteia a diversidade de conceptualizações do currículo e do desenvolvimento curricular, os principais traços característicos das teorias curriculares que se têm sucedido e ou que rivalizam na busca de hegemonia no sector da educação, bem como as políticas educativas e curriculares que vêm sendo concebidas e realizadas à escala global, dispensando atenção particular às dimensões instituinte e instituída do processo curricular. Ainda que fortemente condicionado pelas concepções e políticas de globalização da educação, a tendência para a uniformização educativa e curricular não constitui uma inevitabilidade, demonstrando-se, pelo contrário, que o processo de desenvolvimento curricular deixa espaços de apropriação e inovação ao nível das instituições educativas, atendendo à diversidade de contextos, expectativas e perspectivas inerentes à dinâmica da realização do currículo. Ainda no plano teórico, ao analisar-se a evolução do conceito ou ideia de Universidade, desde a sua génese até aos tempos actuais, coloca-se em relevo a natureza específica da instituição no âmbito do ensino superior, patenteando o modo como, nos diferentes contextos, a mesma tem procurado afirmar a centralidade do conhecimento e do currículo no cumprimento da sua missão, a despeito de factores e condicionalismos diversos, de entre os quais releva o tipo de relacionamento predominante entre a Universidade, o Estado e o mercado, no âmbito do qual se deve entender a complexidade da crise institucional, na triplicidade das suas manifestações (crise de legitimidade, de hegemonia e de identidade) que atravessa a academia, com reflexos ao nível das tendências para o condicionamento da autonomia, missão e funções da academia, assim como da própria natureza do conhecimento universitário. Na procura de saídas para a crise, que é global e, como tal, se reflecte nas universidades do continente africano, em que se insere Cabo Verde, a Universidade é desafiada a afirmar a sua especificidade institucional, enquanto promotora da alta cultura e da capacidade de pensamento de longo prazo, conciliando, deste modo, as suas funções essenciais ou simbólicas com as que se prendem com a satisfação das necessidades imediatas ou de curto prazo da economia e do mercado. Com base nos pertinentes subsídios teóricos, os estudos empíricos desenvolvem-se segundo a abordagem metodológica de estudo de caso, em que a análise documental e as técnicas de investigação qualitativa e quantitativa permitiram consolidar as evidências sobre: (i) os antecedentes da criação da Uni-CV, através do mapeamento do percurso académico e curricular dos diversos estabelecimentos públicos de ensino superior que precederam a universidade pública, legando a esta o seu património científico, tecnológico e logístico, com as inerentes potencialidades e limitações; (ii) o processo de institucionalização da Uni-CV, com a referencialização das opções estruturantes da organização e gestão da Universidade assim como da política educativa e curricular da Universidade; (iii) a experiência multifacetada de desenvolvimento curricular na novel instituição durante os cinco primeiros anos de funcionamento (2006-2011), correlacionando opções e práxis e evidenciando tendências da sua evolução. Da análise interpretativa dos estudos empíricos realizados, mediante a triangulação dos dados de arquivo e de perspectiva, resulta que a Uni-CV, não obstante as fragilidades persistentes no processo de seu desenvolvimento institucional, tem cumprido a sua missão de forma satisfatória, facto que fica a dever-se quer à adequação das opções, normas e directivas conformadoras da dimensão instituinte do processo curricular, quer ao esforço de realização das prescrições curriculares, sendo, todavia, evidentes os desafios a serem vencidos tendo em vista a consecução da almejada excelência académica, que os Estatutos propugnam, e que passa, nomeadamente, pela melhoria do nível da qualificação do seu corpo docente, pela implementação ou funcionamento efectivo de alguns dos órgãos da academia e pela afirmação da investigação científica como função incontornável para o desempenho cabal das funções de ensino e extensão. De entre as conclusões, sustenta-se que, no processo de integração de Cabo Verde nas redes internacionais de investigação e excelência científica e tecnológica, como, de resto, propugnam os Estatutos da Uni-CV, deve atender-se à especificidade deste pequeno país do Atlântico Médio, tendo em conta as suas fragilidades estruturais, pelo que se impõe algum distanciamento crítico em relação à incorporação de certas opções de política educativa e curricular que emanam de instâncias internacionais, independentemente do seu carácter inovador ou mesmo da sua possível consistência científica e técnica, comprovada em outros contextos.

Health-related quality of life in migrant preschool children.

BACKGROUND: Minority groups have a lower health-related quality of life (HRQOL), but there is little information if this finding also applies to children. In this study, we compared HRQOL between young children with and without migrant parents. METHODS: Two cross-sectional studies of culturally diverse preschool populations in Switzerland: Ballabeina (40 preschools, 258 girls and 232 boys aged 4 to 6 years) and Youp'là Bouge (58 child care centers, 453 girls and 522 boys aged 2 to 4 years). Most children were born in Switzerland (Ballabeina: 92.3%; Youp'là Bouge: 93.7%). Number of migrant parents was considered as the main exposure. HRQOL was measured using the 23-item Pediatric Quality of Life Inventory. RESULTS: Children of migrant parents had a significantly lower HRQOL total score (mean ± SD, Ballabeina: 84.2 ± 9.1; 82.7 ± 9.6 and 81.7 ± 11.7 for children with none, one or two migrant parents, respectively; Youp'là Bouge: 83.8 ± 8.6; 82.9 ± 9.5; 80.7 ± 11.7, all p < 0.05). Similar results were found in Ballabeina and Youp'là Bouge for social, school and physical functioning (all p < 0.05), but not for emotional functioning. The differences in HRQOL measures were partly mediated by children's place of birth, parental education, paternal occupational level, children's BMI, screen time and physical activity in one study (Ballabeina), but not in the other (Youp'là Bouge). CONCLUSION: In preschoolers, children of migrant parents have lower HRQOL than children of non-migrant parents. These differences are only partly mediated by other sociocultural characteristics or lifestyle behavior. These families may need assistance to prevent further inequalities.

Profile of male adolescents with conduct disorder on intellectual efficacy, cognitive flexibility, cognitive coping, impulsivity and alexithymia: a comparison with high-risk controls

Background and Objectives: To specify which of the documented cognitive and emotional deficits characterize adolescents with conduct disorder (CD) compared with high-risk controls. Methods: High-risk adolescent males with and without CD were compared on intellectual efficiency, cognitive flexibility, impulsivity, alexithymia, and cognitive coping strategies. Substance use was controlled for in analyses. Results: Both groups showed normal intellectual efficiency and cognitive flexibility, as weil as heightened alexithymia and bebavioral impulsivity. Youths with CD evidenced more self-defeating and black-and-white tbinking under stress, and more acting-out under negative affect, than those without CD. Conclusions: Deficits specifie to CD resided in facets of emotional functioning and cognitive coping that might be targeted by a coping skills intervention.

Seasonality of insects in the semi-arid Caatinga of northeastern Brazil

Insects are essential to tropical ecosystems functioning. In semi-arid regions, the increase in abundance and/or activity (e.g. reproduction and foraging behavior) of insects is usually associated with climatic variables. The present study investigates which climatic variables are best predictors of insect abundance in an area of Caatinga in northeastern Brazil. Individuals were sampled for 24 months using Malaise and pitfall traps, and beating trays. A total of 58925 individuals belonging to 20 insect orders were collected. The most abundant orders were Hymenoptera, Diptera, Collembola and Coleoptera. Most orders studied showed a clear maximum abundance in the rainy season. Rainfall and humidity were the best predictors of insect abundance in the Caatinga. However, no climatic variable could explain Psocoptera and Blattodea variance in abundance/activity. Our results suggest that climatic changes associated with rainfall patterns in the Caatinga may affect ecosystem processes and services that depend direct or indirectly on insect abundance/activity.

Prophylaxie de l'endocardite infectieuse : apport du modèle expérimental

Il est admis que l'endocardite infectieuse devrait faire l'objet d'une prophylaxie antibiotique du fait d'une morbidité et d'une mortalité non négligeables. Le choix de cette prophylaxie repose sur l'identification (i) des patients à risque, (ii) des interventions médico-chirurgicales pouvant provoquer une bactériémie, (iii) du régime prophylactique le plus efficace et (iv) du rapport entre le risque des effets secondaires des médicaments et celui de développer une endocardite infectieuse. Les patients à risque et les interventions médico-chirurgicales provoquant une bactériémie ont été identifiés par des études cliniques. En revanche, l'efficacité de la prophylaxie n'est fondée que sur les résultats de modèles animaux. L'expérimentation animale a contribué à une meilleure connaissance des mécanismes de pathogenèse de l'endocardite infectieuse. Elle a permis de comprendre le mode d'action des antibiotiques dans la prévention des endocardites infectieuses et de jeter les bases d'une antibioprophylaxie raisonnée et adaptée aux différents patients à risque. It is commonly agreed that infectious endocarditis should be handled by antibiotic prophylaxis whenever possible because of its significant morbidity and mortality rate. The choice of the type of prophylaxis depends on the identification (i) of the patients with risk factors (ii), of medico surgical procedures possibly causing bacteremia (iii), of the most efficient prophylactic program and (iv) of the balance between secondary effects of medication and the risk of developing infectious endocarditis. The patients with risk factors and the medico surgical procedures causing bacteremia have been clearly identified by clinical research, whereas efficiency of prophylaxis is only established on the results of animal models. Animal experimentation contributed to a better understanding of the mechanisms of pathogenesis of infectious endocarditis. It made it possible to understand the functioning of antibiotics in the topic of the prevention of infectious endocarditis and to settle the basis of a judicious antibiotic prophylaxis adapted to the various patients with risk factors.

Identification and Characterization of Natural Anti-Breast Cancer Compound: Costunolide

Breast cancer is the most common cancer among women, 23% (1.3 million) of the total of new cases and the second leading cause of cancer death in women exceeded only by lung cancer. Natural medicines have been proven to be a central source of narrative agents with a pharmaceutical potential. Costunolide is sesquiterpene lactones consisting of diverse plant chemicals that exhibit anti cancer action through cytotoxic effects on various cancer cells. The objectives of present study were to explore the effects of natural compounds on the proliferation of MCF-7 cells and to determine the role of ROS in natural compounds-induced apoptosis in breast cancer cells with a therapeutic potential. Results showed that costunolide screened, possess potent anticancer properties against breast cancer MCF-7 cells, Costunolide was observed as strong anti-proliferative agent with IC50 = 50µM. The anti-proliferative effect of costunolide on MCF cells was confirmed by live/dead assay using fluorescent probes calcein AV/PI. The results demonstrated that treatment of cells with costunolide decreased the viability of MCF-7 cells in a dose-dependent manner. To determine the costunolide-induced apoptosis, flow cytometric analysis was carried out. The results showed that costunolide induced apoptosis in a dose-dependent manner in breast cancer MCF-7cells. ROS are well known mediators of intracellular signaling of cascades. The excessive generation of ROS can induce oxidative stress, loss of cell functioning, and apoptosis. In the present study, we assumed that costunolide might arouse ROS level, which could be involved in induction of apoptosis. Therefore, the intracellular ROS level was measured using the ROS-detecting fluorescence dye 2, 7-dichlorofluorescein diacetate (DCF-DA). Interestingly these effects were significantly abrogated when the cells were pretreated with N-acetyl- cysteine (NAC), a specific ROS inhibitor. Costunolide induces apoptosis through extrinsic pathway in MCF-7 breast cancer cells, In order to examine whether costunolide suppresses cell growth inducing apoptotic cell death, we analyzed DNA contents and apoptosis-related proteins expression level by flow cytometry and western blot, respectively in MCF-7 breast cancer cells we investigated whether costunolide activates extrinsic apoptotic pathway. We examined the expression levels of death receptor signaling-related proteins, caspase-3, and PARP. The results showed that procaspase-3 was cleaved to yield 17 and 20kDa fragments and activation of PARP in treated cells with 25 and 50μM of costunolide. Costunolide induce apoptosis through intrinsic mitochondria pathway in MCF-7 breast cancer Cells. We examined the expression levels of mitochondrial apoptotic pathway related proteins such as anti-apoptotic protein, B-cell lymphoma protein-2 (Bcl2), and pro-apoptotic protein Bax. Costunolide involved in the down regulation of Bcl-2 and up regulation of Bax. These results suggest that costunolide may have beneficial effects for the reduction of breast cancer growth, and new therapeutic strategy for the treatment of human cancers.

Predictors and Moderators of Clinical Outcomes in Adolescents with Severe Mental Disorders After an Assertive Community Treatment.

Previous studies have shown that stressful life events (SLEs), gender, social functioning and pretreatment severity are some of the predictors and/or moderators of treatment outcome in psychiatric care. The current study explored the effect of these predictors and moderators on the treatment outcome related to assertive community treatment (ACT) proposed to young people with severe mental disorders. 98 patients were assessed for externalizing and emotional difficulties, at admission and then at discharge of an ACT. Analyses revealed significant improvements in terms of symptomatology. In particular, regression analyses showed that pretreatment severity is a significant predictor of the outcome on emotional symptoms and is moderated by SLE on the outcome on externalizing symptoms. Furthermore, higher social functioning proved to predict better outcome on externalizing symptoms. Our results further evidence that these factors can explain inter-individual differences in outcome related to ACT. The theoretical and clinical implications of these results are discussed.

Managing by values in the next milenium: Cultural redesign for strategic organizational change

The system of beliefs and values, that shaped the model for management and organizations during the 20th century, is just not good enough today. In order to keep a business functioning well and competing successfully in markets that are increasingly more global, complex, professionally demanding, constantly changing and oriented towards quality and customer satisfaction a new model is needed. In this paper, we will propose that both Management by Instructions (MBI) and Management by Objectives (MBO) today give notoriously inadequate results. By contrast, description of a new approach labeled: Management by Values (MBV), seem to be emerging as a strategic leadership tool. The paper outlines this approach and discusses the implementation of MBV as a tool to redesign culture in organizations and prepare them for the next millenium.

The political consequences of unemployment

We analyze the channels by which an ill-functioning labor market changes the preferences of the people for public policy and therefore the decisions that are made. We not only discuss labour market reform but other important aspects of policy making such as the size and structure of government spending. Theclass of mechanisms that we highlight can be summarized as the very existence of unemployment generating political support for "sclerosis". This may help to explain the timid pace of reform, in particular the fact that any recovery sends them at the backfront of the political agenda, and the sometimes violent opposition generated by some measures, as we have seen mostly in France.

Hippocampal volume predicts fluid intelligence in musically trained people.

Recently, age-related hippocampal (HP) volume loss could be associated with a decrease in general fluid intelligence (gF). In the present study we investigated whether and how extensive musical training modulates human HP volume and gF performance. Previously, some studies demonstrated positive effects of musical training on higher cognitive functions such as learning and memory, associated with neural adaptations beyond the auditory domain. In order to detect possible associations between musical training and gF, we bilaterally segmented the HP formation and assessed the individual gF performance of people with different levels of musical expertise. Multiple regression analyses revealed that HP volume predicts gF in musicians but not in nonmusicians; in particular, bilaterally enhanced HP volume is associated with increased gF exclusively in musically trained people (amateurs and experts). This result suggests that musical training facilitates the recruitment of cognitive resources, which are essential for gF and linked to HP functioning. Musical training, even at a moderate level of intensity, can thus be considered as a potential strategy to decelerate age-related effects of cognitive decline. © 2013 Wiley Periodicals, Inc.

Homéostasie, marqueurs somatiques et intentionnalité : le statut de la représentation et ses implications en psychanalyse et en neuroscience

Résumé : Si la psychanalyse est régulièrement remise en cause pour son manque de fondement scientifique, de nombreux travaux issus des neurosciences en appellent paradoxalement à un retour aux thèses freudiennes. Cette étude se propose, dans ce contexte, de revisiter les bases neurobiologiques de la métapsychologie et de montrer comment celle-ci repose sur une conception homéostatique du vivant. On en tire plusieurs conséquences. Premièrement, contre Brentano, selon qui l'intentionnalité est la marque du psychologique, on propose que celle-ci s'avère être, plus originellement, la marque des régulations biologiques. Deuxièmement, on montre comment Freud et Damasio développent des conceptions similaires sur le fonctionnement homéostatique de la cognition. Sur le plan épistémologique, on plaide en faveur de la complémentarité de ces deux approches. Si Damasio met au jour les variables somatiques permettant de mesurer les effets de la vie psychique, la théorie pulsionnelle permet de dépasser les problèmes liés à l'ambiguïté de la notion de «représentation cérébrale ». C'est à partir de cette thèse que l'on peut, selon nous, appréhender la psychanalyse comme un double projet visant à articuler une naturalisation de l'appareil psychique à une herméneutique de ses productions. On considère cette double visée comme une réponse à la difficulté centrale que rencontrent les sciences de l'esprit quant aux conditions de possibilité d'une naturalisation de l'intentionnalité. A partir de cette problématique, il devient pertinent d'évaluer la solution freudienne à la lumière de la posture intentionnelle dennettienne et de la théorie gazzaniguienne de l'interpreter. II ne s'agit pas, selon ces dernières approches, de naturaliser directement l'intentionnalité, au risque de commettre une erreur de catégorie. Il est question, au contraire, d'utiliser les principes du fonctionnement homéostatique comme autant de «règles »interprétatives permettant, sur le plan psychologique, de construire du sens. On trouve enfin dans le modèle de l'espace global de travail un moyen de remettre au goût du jour la conception freudienne, dynamique et conflictuelle, du fonctionnement psychique. On avance enfin, à partir de ce modèle, des hypothèses sur les mécanismes cérébraux susceptibles de sous-tendre l'efficacité thérapeutique de la cure analytique. Abstract : While Psychoanalysis' scientific basis is open to question, some neuroscience works are paradoxically calling for a return to Freud. Therefore, the first aim of our study consists in revisiting metapychology's neurobiological roots and to show how it is grounded on a homeostatic theory of life. Several consequences can be drawn from this statement. Firstly, in opposition to Brentanian definition of intentionality, as the specific mark of psychology, we argue that it is more specifically the mark of biological balance. Secondly, this statement allows to show how Freud's and Damasio's theories share common views on the homeostatic functioning of cognition. From an epistemological point of view, they complete one another. If Damasio has highlighted the measurable somatic variables from which we can infer psychic life, the theory of drives allows conceptual difficulties linked to the use of the ambiguous notion of "cerebral representation" to be overcome. According to us, this thesis leads psychoanalysis to be approached as a twin project aiming to articulate psyche naturalization, to a hermeneutic of its productions. It maybe seen as a way to respond to the central issue of mind sciences, that is, to account for the naturalization of intentionality. Given this theoretical framework, it seems relevant to reconsider freudism in the light of the dennettian intentional stance and the gazzanigan theory of interpreter. Then, freudism can be seen as a way to avoid a category mistake. Its solution rejects direct intentionality naturalization in favor of a construction of sense. In this framework, interpretation is regulated by the rules abstracted from the homeostatic functioning of life. Furthermore, we show how the dynamic and conflictual Freudian psyche can be evaluated using the Global workspace model, which allows us to put forth hypotheses on the cerebral mechanisms that may underlie the efficiency of analytical cure.

Translation to success of surgical innovation.

Contemporary thoracic and cardiovascular surgery uses extensive equipment and devices to enable its performance. As the specialties develop and new frontiers are crossed, the technology needs to advance in a parallel fashion. Strokes of genius or problem-solving brain-storming may generate great ideas, but the metamorphosis of an idea into a physical functioning tool requires a lot more than just a thinking process. A modern surgical device is the end-point of a sophisticated, complicated and potentially treacherous route, which incorporates new skills and knowledge acquisition. Processes including technology transfer, commercialisation, corporate and product development, intellectual property and regulatory routes all play pivotal roles in this voyage. Many good ideas may fall by the wayside for a multitude of reasons as they may not be marketable or may be badly marketed. In this article, we attempt to illuminate the components required in the process of surgical innovation, which we believe must remain in the remit of the modern-day thoracic and cardiovascular surgeon.

Prediction of functional outcome 18 months after a first psychotic episode: a proton magnetic resonance spectroscopy study.

CONTEXT: Recent magnetic resonance imaging studies have attempted to relate volumetric brain measurements in early schizophrenia to clinical and functional outcome some years later. These studies have generally been negative, perhaps because gray and white matter volumes inaccurately assess the underlying dysfunction that might be predictive of outcome. OBJECTIVE: To investigate the predictive value of frontal and temporal spectroscopy measures for outcome in patients with first-episode psychoses. DESIGN: Left prefrontal cortex and left mediotemporal lobe voxels were assessed using proton magnetic resonance spectroscopy to provide the ratio of N-acetylaspartate (NAA) and choline-containing compounds to creatine and phosphocreatine (Cr) (NAA/Cr ratio). These data were used to predict outcome at 18 months after admission, as assessed by a systematic medical record audit. SETTING: Early psychosis clinic. PARTICIPANTS: Forty-six patients with first-episode psychosis. MAIN OUTCOME MEASURES: We used regression models that included age at imaging and duration of untreated psychosis to predict outcome scores on the Global Assessment of Functioning Scale, Clinical Global Impression scales, and Social and Occupational Functional Assessment Scale, as well as the number of admissions during the treatment period. We then further considered the contributions of premorbid function and baseline level of negative symptoms. RESULTS: The only spectroscopic predictor of outcome was the NAA/Cr ratio in the prefrontal cortex. Low scores on this variable were related to poorer outcome on all measures. In addition, the frontal NAA/Cr ratio explained 17% to 30% of the variance in outcome. CONCLUSIONS: Prefrontal neuronal dysfunction is an inconsistent feature of early psychosis; rather, it is an early marker of poor prognosis across the first years of illness. The extent to which this can be used to guide treatment and whether it predicts outcome some years after first presentation are questions for further research.

LRF-mediated Dll4 repression in erythroblasts is necessary for hematopoietic stem cell maintenance.

Hematopoietic stem cells (HSCs) are the most primitive cells in the hematopoietic system and are under tight regulation for self-renewal and differentiation. Notch signals are essential for the emergence of definitive hematopoiesis in mouse embryos and are critical regulators of lymphoid lineage fate determination. However, it remains unclear how Notch regulates the balance between HSC self-renewal and differentiation in the adult bone marrow (BM). Here we report a novel mechanism that prevents HSCs from undergoing premature lymphoid differentiation in BM. Using a series of in vivo mouse models and functional HSC assays, we show that leukemia/lymphoma related factor (LRF) is necessary for HSC maintenance by functioning as an erythroid-specific repressor of Delta-like 4 (Dll4) expression. Lrf deletion in erythroblasts promoted up-regulation of Dll4 in erythroblasts, sensitizing HSCs to T-cell instructive signals in the BM. Our study reveals novel cross-talk between HSCs and erythroblasts, and sheds a new light on the regulatory mechanisms regulating the balance between HSC self-renewal and differentiation.